This is a community-based study to evaluate heterosexual sexual activity as a major risk factor for acquisition of HIV infection among sexually active women in the San Francisco Bay Area. Research goals include determining the point prevalence of HIV infection in several sexually active groups of females, including women of all racial groups, sex workers, IV drug users, women who use drugs such as alcohol and crack cocaine but do not inject drugs, as well as women with sexual partners with known high risk behavior of HIV infection in women, and the potential for behavior change among participants in a peer-provided intervention program. Specifically, AWARE proposes to: a) recruit 400 additional high risk women and 30 seropositive women during years 01 and 02 from Bay Area sites not previously included in prior efforts as well as 200 from sites with surveillance rate information available from previous work, c) interview, counsel new participants about sexual and drug use behavior associated with AIDS risk, and obtain HIV-related serological and physical examination data, d) provide, encourage participation in, and assess effectiveness of two intervention programs designed to reduce HIV transmission risk, e) follow this group and ongoing AWARE participants semiannually, to monitor behavior change and change in health status, and f) analyze and report predictors of infection, behavior change, and progression of HIV infection among women, and assess whether these differ for subgroups of interest, specifically women of different racial/ethnic groups, and women with different risk circumstance or cofactors for HIV transmission, such as drug use that is not IV, working in prostitution, prior or concurrent STDs or other vaginal infections, and pregnancy.